I couldn't disagree with you more. Ryder showed the spirit, determination, passion, and grit of Jo as none other had in the filmed role. (Katharine Hepburn came closest, but she wasn't at the top of her craft at that moment, as Ryder was.)
That Ryder does have looks (as did Hepburn in 1936) doesn't make her character's protestations of being "ugly" any less valid or believable -- for the issue in the story is how she sees and values herself. We all have crises of self-image and self-worth. Alcott's writing, and Ryder's acting, was vivid on this score.
Ryder deserved the Oscar she was nominated for in 1994. This version of "Little Women" is not quite a straight retelling of the story -- it's fleshed out with details from the real Alcott's life -- but it's closest to the author's spirit. Especially in her writing herself into the story as Jo.
That version also had Susan Sarandon as the girls' mother, and, o'course, that's enough for some of the politicizers of art around here to trash it, sight unseen -- or even seen and unobserving. And Sarandon's astringent acting improved on the depiction of Marmee in the book, who was impossibly sweet even for the 1870s.